Foam-type fire extinguisher



Jan. 13, 1931. I w. H. BANFIL 1,788,375

FOAM TYPE FIRE EXTINGUISHER Filed July 21, 1926 /J/l/ ///////////l Patented `lan. 13, 1931 VwntLrAivr n. BANFIL, oFKBosToN, Massachussets j FOAM-TYPE Finn EXTINGUISHER Application inea July 21, 1926. l serial 110,123,956.

`This invention relates to fire extinguisherstaineris'not immediate but only after an eX- of the foam producing type and particularly relates to the portable or hand type of foam producing fire'extinguisher.

A foam producing lire extinguisher ofthe hand type comprises a casing adapted to contain a gas generating' and foam producing liquid as a water vsolution of sodium bicarbonate and licorice, and an vinner receptacle or as aluminum sulphate, which, when caused to min with the foam-producing liquid, generates a. foam and a gas whichV expels the foam through the hose Aof the casing. By reason ofthe characteristics of the foam propreferably should approximate the- 'amount of foam producing solution; consequently the acid container or tube has substantial internal diameter and is approximately coenten` sive with tl e height of the casing. The open top of the said container is normally disposed above the liquid levels and is normally closedV side and then' given coating of lead either byA dil ping the' tinned containerin a bath of molten lead or by lapplying molten lead to the tinned surfaces'. the container is uniformly coated with a thin coating of lead; and the intended purpose of the lead coating is vto protect the brass tube against the action of the acid.

The lire extinguisher is'adapted to be maintained charged, in readiness for instant use and, when discharged, usually is immediately recharged, so that the acid container is con tinually filled with a charge of acid. Itis found in practice that the acidl container is not entirely acid-resistant but is slowly eaten away in spots, not only at the liquid level, but also below thelevel, and finally allows the liquids to commingle and discharge foam, thereby resulting in a possible damageto surrounding objects. The failureof the contube adapted to contain an acid or reagent,

ducing materials, the amount of acid solution Under these conditions tended period of time. 1 Some containers fail in a few months and others in `one or two years. Such a container cannot be con` sidered to be entirely satisfactory as the ultimate and unintentional discharge of the ei;-

.tinguisher is always present .and the containers must be replaced from time to time at an expense to the user.

Consequently it is an object of this vinvention to provide an acid container for a foamproducing type of fire extinguisher characterized by being immune or inert to the acid it is adapted to contain, so that it will be acidtight for an indefinite period of time.

In carrying out'this obj ect of the invention in practice, l. provide an acid container composed of an acid-immune or inert vitreous material referabl O'lass which has ai" proirimately the height of the extinguishercasing and is of large internal diameter to contain the requisite supply of acid.

lt is afurther object of the'invention to provide a protective holder for the acid container and, to this end the glass container is removably received snugly within a stiif metal fluid tight tube or shell and rests upon the bottom thereof and has litsside walls supported substantially throughout by the side wall of the tube. VThe protective tube may be composed of brass and may be lead coated. A further object is to provide means to hold the glass container removably in place within the protectiveliolder.

It is a further object vof the invention to provide a gravity-operated closure forv the glass acid container, Vwhich closuroalso is composed of an acid-inert material and, to this end, l formftlle closure of a vitreous material as glazed porcelain.

A further objectis theprovision for the seating of the closure directly upon the glass container and for a secondary seat of the closure upon the holder for thecontainer, so that the holder can serve temporarilyas the acid container and beclosed by the closure, in the remote vevent of the breaking ofthe glass container.v

A yet furtherobiect of the invention is the permanent enclosure of the closure in a lll A further obJect is generally to improve` the construction of lire extinguishers.

Fig. 1 is a sectional elevation through Va fire extinguisher embodying the invention.

lfig. 2 is a side elevation in detailof the valve cage.

Figi); is a section along line 3-3 of Fig. 1.

4 is a sectional detail of the acid container and associate-d elements, in the inverted position thereof, and illustratingparticularly the-position assumed by the closure.

As here shown, the fire extinguisher embodying the invention includes a casing which is adaptedto Vcontain the foam and gas producing materials, as a water solution of sodium bicarbonate and licorice. The casing is closed atthe bottom and is provided at the top with an open and externally screw-threaded neck 12 whichis removably closedby a cover 14 that is screw-threaded on said neck and is provided with a hand wheel 16 by which the cover can be rotated on thev neck.v A gasket. 1,8 is interposed between the neckv and the cover to provide a fluid-tight joint thereat. y

A valve cage for the closure of the acid container is carriedV bythe cover and comprises a metal tube 2O having a diameter approximating thatof the neck-opening and permanently affixed as by solder or brazing material to the under side of the cover and depending .therebeneath within the neckopening. A collar 22 is secured permanently Vto the lower end of said tube and is pro- Y vided with a radially.inwardly-directed annular flange 24 which extends into the interior of the tube'and cooperates with the cover to provide permanent closures or barriers at the :ends of the tube to retain mov- Y ably therein the closure for the acid contain- I er, `The side wallof .the tube isprovided with a plurality of openings or ports 26 of substantial dimensions separated by ribs 28 which serve as guide members for the closure during its movements. 7

The closure for the acid container comprises a relatively discoidalmember 30 composed of an acid-inert material, preferably glazed porcelain and adapted to lit loosely. within the valve cage and, when the cage is4 inverted, to-fall from the position illustrated in Fig. 1 to that .illustrated in Fig. 4. The closure is provided with an upstanding annular flange 32 that is adapted to engage with the side-of thecage and prevent the cramping or jamming ofthe closure in the cage. The-top portion of the valve cage is adapted toV provide a compartment in which the closure is adapted to rest, in the inverted position of the extinguisher, in which position the closure is mainlybelow the ports, so that the port-s are freely open, although there is a suiiicient extent of the closure accessible Vat the ports to enable the closure to be manipulated by hand ifit should stick in the openposition before the extinguisher has 4been cleaned after being operated. The botcontainer.

VThe holder forV the acid container comprises a metal tube 38 which is closed at the bottom and is open at the top and is axially disposed within and extends approximately coextensive with the length of the casing 10. The holder preferably is'composed of brass and has a` coating of lead upon its surface. rhe upper end of said holder,'about the top thereof, is provided with an externally screw-threaded ring 40 which is permanently affixed to the holder. vSaid ring is adapted to be screw-threaded removably into the internally screw-threaded lower end 42 of the collar 22 and aga-inst the flange 24thereof, thereby to secure the holder removably connected with the valve cage and thereby to cover 14. l -f The acidcontainer comprises an elongated tube 44 which is composed of an acid-immune and vitreous material, preferably glass. The glass tube is of substantial thickness, for mechanical strength and is received snugly and removably within the holder 38Y and rests vupon the bottom and is supported over practically its entire height by the side wall of the holder. The glass tube is closed at the bottom and is open at the top. The open top is somewhat drawn in or is provided with a neck 46 which is received within the valvev cage and is terminated above the flange 24 in a fiat seat 48against which the inclined valve face 56y of the closure is adapted to rest, in the normal position of the extinguisher, thereby to seal the tube. In this position thel lower edge of the closure is spaced above the flanve 24A and, in the remote possibility of the glass tube becoming broken, the closure can seat kon the flange, thus maintaining the seal on the acid.

The glass tube normally Vis retained in position within its holder by said flange 24 which is adapted for engagement with the neck 46 of the tube. VJhen, however, the holder is unscrewed from the valve cage, the ,glass tube can be removed readily from the holder. y

- Since the acid container and its associated elements are connected with and carriedv by the cover 14,` they can be'removed'readily from the extinguisher casing when the ex- Vis thereby free from accidental discharge and from container replacements.

The construction may be otherwise modilied without departing from lthe spirit of the invention.

I claim:

l. In a foam-type fire extinguisher of the type having an outer casing adapted to contain the foam-producing liquid, a holder comprising a long open-top, closed bottom fluid-retaining metal tube adapted to be disposed within said casing and to extend approximately co-extensive with the length thereof, and an acid-containing glass tube removably received snugly Within said tubular holder and having an upper open end terminated shortly above the open top of said tube, a gravity-operated closure for said glass tube arranged to seat directly on the open top thereof, and means to retain said holder in the aforesaid relation.

2. In a foam-type fire extinguisher of the type having an outer casing adapted to contain the foam-producing liquid, a holder comprising a long open-'top closed-bottom fluid retaining metal tube adapted to be disposed within said casing and to extend approximately co-extensive with the length thereof, and an acid-containing glass tube Y removably received snugly within said tubular holder and having an upper open end terminated shortly above the top of said tube, a collar having ak removable connection with the top of said holder and having an inwardly directed flange which overlies said glass tube, below the open top thereof and serves to retain saidy tube Within said holder, a ported valve-cage having a connection at its lower end with said collar above said flange, and a gravity-,operated closure for said glass tube slidable in said cage and arranged to seat directly on the open top of said glass tube.

` 3. In a foam-type iire extinguisher of the type having an outer casing adapted to contain the foam-producing liquid, a holder comprising a long open-top fluid retaining inet-al tube adapted to be disposed within said casing and to extend approximately coextensive with the length thereof, a ported valve cage disposed above and having a removable screw-threaded connection with and surrounding the open top of said holder, said cage having an inwardly directed flange, a glass acid-containing tube'removably contained snugly within said holder and having its upper open end disposed within and extended above said flange, and

a gravity-operated closure for the opentopsiV y of both said glass and metal tubes movably disposed in said cage above said flange.

4. In a foam-type fire extinguisher, an open top casing adapted to contain a foamproducing liquid, a removable cover for said casing, a tube havingports in its side wall connected permanently with said cover and depending therebelow into said casing, a collar permanently attached to the lower end `of said ported tube having, an inwardly directed flange and an internallyscrew-threaded section immediately beneath said flange, an open-top fluid retaining metal tubular holder disposed beneath said ported tube and having its upper end screwthreaded removably in the screw-threaded section of said collar and seated against said flange, an acid containerv received removably within' said fluid retaining holder andxhaving a reduced open top extended above said flange,V and a lgravity-operated closure for said acid container movably vdisposed in said ported tube and overlying said flange. W f

5. ln a foam-type lire-extinguisher, a fragile acid container having an open top, a metal liquid-retaining holder enclosing said container having an open top disposed beneath thetop of said fragile container, and a closurefor said container extended peripherally therebey'ond and above and in position also to engage the top of and close said niet-al holder if said fragile container should break.

6. inv ak lire extinguisher of the foam-producing type, the combination of a long and narrow cylindrical fluidV retaining metal tube which is open at the top and has external screw threads at the top, a cylindrical metal valve cage having ports in its cylindrical wall and open at the bottom aligned with said tube and having a ring surrounding its open bottom provided with internal screw lthreads in which theexternal vscrew'threads of said tube are received, said ring having an internal ledge which overlies the top of said tubeand extends inwardly over the open top thereof and constitutes seat against whichsaid tube is screwed, a cylindrical fluid retaining glass tube open at the top snugly'received removably within said metal tube'and supported at the bottom and sides thereby, said glass tube having its side wall at the top flared inwardlyand located within said internal ledge and abutting thereagainst, said ledge thusv consituting means to hold said glass tube in place within said met-al tube when both are inverted, the top face of said glass tube being horizontal and constituting a valve seat, and

a gravity-operated valve contained loosely and slidably within said valve cagehaving a bottom face which is seated normally upon the valve seat of said glass tube', said valve also overlying and normally spaced above and out of engagement with said ledge.

ico

CII

7. In a fire extinguisher of the foam-producing type, the combination ofa long and narrow cylindrical iuid retaining metal tube Which is open at the top and has external screw threads at the top, a cylindrical metal valve cage having ports in its cylindrical Wall and open at the bottom aligned with said tube and having a ring surrounding its open bottom provided with internal screw threads in which the external screw threads ont said tube are received, said ring having aninternal ledge which overlies the top of said tube and extends inwardly over the open top thereof and constitutes a seat against which said tube is screwed, a cylindrical Huid retaining glass tube open at the top snugly received removably Within said metal tube and supported at the bottom and sides thereby, said glass tube having its side Wall at the top flared inwardly and located Within said internal ledge and abuttingthereagainst, said ledge thus constituting means to hold Ysaidglass tube in place Within said met-al tube whenvboth are inverted, the top 'face of said glass tube being horizontal and constituting a `valve seat, and a gravity-operated valve contained loosely and slidably Within said valve cage having a bottom face which is seated normally upon thevalve seat ot said glass tube, said valve having a depending annular rini Which `protrudes belovv said seat into the space between the top ot said glass tube and said cage and over and normally rfree from contact With said ledge, said rim'and ledge adapted to engage and to constitute a supplementary valve to seal said metal tube in the event of breakage of said glasstube. v

'8. In a foam-type fire extinguisher of the type having an outer casing adapted to'contain the foam-producing liquid, a long acid container adapted to be disposed Within said casing and to extend approximately co-extensive With therlength thereof and consisting of an inner open-top fluid-retaining shell adapted to contain the acid and characterized by being inert With respect to the acid, and an outer fluid-retaining, open-top and closed-bottom metal tube enclosing saidl shell and engaging it along'its length and providing mechanical support therefor, said shell having an' internal acid-resistant coating whereby said shell can also serve as an acid container in the event of breakage of said inner container.

In testimony whereof, I have signed my name to Vthis Vspeciiication.

WILLIAM H; BANFIL. 

